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Fundamental bounds on quantum measurements with a mixed apparatus

S. Bose·V. Vedral
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Abstract

We consider the apparatus in a quantum measurement process to be in a mixed state. We propose a simple upper bound on the probability of correctly distinguishing any number of mixed states. We use this to derive fundamental bounds on the efficiency of a measurement in terms of the temperature of the apparatus.

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S. Bose, V. Vedral. 2000-04-04. Fundamental bounds on quantum measurements with a mixed apparatus. https://arxiv.org/abs/quant-ph/0004016

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